I am looking at updating the heating and water heating systems in a rental home I recently purchased. Currently, there is a 4 year old Burnham oil furnace with a coil for water heating. I'm looking at adding a natural gas burner to the system, as gas lines are already in place. With regard to water heating, I'm looking at indirect fired systems although I've received some recommendations for installing an electric tank. Thoughts or advice? As you can probably tell, I'm new to this! Thanks.
I have been using Rheem or State or Brad/white PVC flued tank type hot water heater abit more than 61% tank type but less than 1/2 of a tankless. can take -50 PA in the CAZ test and is cheap to flue and works well. You have to plug it in but that not hard in a basement and still takes a 1/2" gas line un like most tankless take 3/4" or 1". I get the PVC flued hot water heater to pass the CAZ test each time.
What are the prices for gas and electricity?
Posted something earlier, but account was hacked. Natural gas tank heater, such as: http://www.kenmore.com/kenmore-elite-50-gal-12-year-natural-gas/p-0...
NG tank probably the way to go in most utility cost situations. Tankless may make sense - about 20% more efficient than standard tank heaters, but beware their usual shortcomings.
Could it be that you have a boiler with tankless coil? Boilers are for hydronic heating, furnaces are for forced air heating.
Is this a single family residence? Will you live in it or rent it out? Year round use?
How many bathrooms, fixtures, what flow rates, how many people in the home, etc.?
What are your goals? Best hot water comfort? Lowest operating cost? Lowest investment cost? Greenest? Any government and utility incentives in you area?
A tankless coil boiler is the cheapest investment, but has the highest operating cost as you are keeping the complete unit hot year round day and night. Plus they are typically not well insulated. Keeps you basement warm and dry. Very limited capacity. Converting it to gas only addresses one of its problems.
Are including the Efficiency Maine cash rebates of up to $300 in your calculation? Are you sure each of these units will actually supply enough hot water to meet peak demand? Have you thought about annualized lifecycle cost = (installation cost + lifespan x Annual fuel consumption in $)/lifespan? Considered controlling demand / consumption (i.e. comfortable ultra low shower heads 1.5 or 1.5 GPM at $20 each, lower flow faucets) already? With 5 occupants what about falling film heat recovery (Google GFX or PowerPipe) to further reduce demand? Are you aware of the pro & cons of each type of system?
If not, you might do well to consult a reputable Building Analyst such as Bo Jesperson at the Breathable Home to help you better understand the implications of these options and perhaps others before you pull the trigger.
Cost & comfort effective DHW is not as simple plug & play replacement anymore.
Best of luck from a coastal Maine Certified Building Analyst.
I see you're in CA but, I didn't see passive solar water heater on the list of viable options? They can be implemented with existing tanks or even supplemented with a tank-less unit for so many residents. They're able to be configured in a multitude of ways & upfront costs. Just thought I would add that to your daunting list of choices. Here is some very basic info on them...http://www.mysolarpower.info/water-heaters.htm
Oops, I just saw that the rental is in Maine but, you are in CA. An active solar heater would be an option but, probably not the most cost effective solution. I know of folks in Alaska that use solar energy for their hot water needs even in their dead of winter, (DIY friends) so I know it is viable even in those conditions. Anyway, if you want to explore it at all for this, or future projects, http://www.energystar.gov/index.cfm?fuseaction=find_a_product.showP... is a good starting point too.
Do you pay for the fuel or does the tenant? If the tenant pays the fuel then leave the 4yr old unit alone. As a landlord you will never get enough extra in rent to justify the expense of replacing such a new system.
My suggestions is to find a gas powered heat pump. We need to avoid burning electricity for heat whenever possible. If you put the same amount of electricity in a heat pump, you can pump 4 times more heat in a climate like California. Google for "gas powered heat pump with water heater" and you'll an expert in not time!
Water heating is typically the second most energy demanding equipment in your home with heating and cooling being first. Going to electric water heater is a very costly endeavor as electric heating can be 3 - 4 times the cost of natural gas heating. It really does depend on what the kWh cost is from your utility as to how much more costly it is.
In California, most electricity is generated from natural gas plants, and about 30% efficiency is lost in this conversion, and another 20 - 40% is lost transferring electricity over transmission lines. Thus the higher cost for kWs of electricity versus therms of natural gas.